Rotary ventilator



Aug. 21, 192s. 1,681,343 W. F. HIRSCHMAN ROTARY VENTILATOR Filed Aug.10, 1926 3 Sheets-Sheet 1 @Normas Aug. 21, 1928. 1,681,343 W. F.HIRSCHMAN ROTARY' VENTILATOR Filed Aug. l0I 1926 5 Sheets-Sheet 2 o/-ar'l I o o 0 3e ,4f/,L 5s

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`W. F. HIRSCHMAN ROTARY VENTILATOR 3 Sheets-#Sheet 3 Filed Aug. 10, 1926!II IllH MFT* fdl

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Patented Aug. 21, i928.

XNII'JLLILfiNI F. HIBSCHMAN,OF LERQY, NEW YORK.

ROTARY VENTI'LATOB.

Application filed August 10, 194246. Serial No. 123,384.

This invention relates to a rotary roof ventilator' which is adaptedtoutilize the pressure of the wind or air currents to dra-w out or suckobjectionablegases or foulair from the building on which it is installedand discharge the same into the outeratmosphere. This invention is animprovement on the ventilatoi'for which Letters Patent were granted tome on 16, 192:2, bearing the number l,4l 6295,.and onthe ventilator forwhich .l filed an application for patent7 Serial No. 348, led January 3,1925.

It isfthe purpose ofthe invention to provide arotary ventilator of thist-ype in which is` mounted a. fan driven by aneleetric motor which is`automatically energized when the velocity Vofthe/wind is insufficientto maintain apredetermined minimum speed and properly ventilate'thebuilding, and which is automatically stopped when the velocity ofthewind increases sufficiently to drive the ventilator at a proper speed.

vFurther objects are to accomplish this purose by means which V ble'toget out of order, whi chdo not Vimpede the fiow of foul -air through theventilator, and whichare adaquately protected from the wind and rain.

'In the accompanying drawings:

Figure l is aI side .elevationof a ventilator' and stack made inaccordance with my in vention, `and showing a part of the same brokenaway and thereof. Figure 2 is a. longitudinal vertical section ofthemercury tube switch which operatesthrough the centrifugal force of ther'otary turret to energize the motor when the wind drives the turret atan insufficient speed. Figure 3 is a horizontal section through theturret support-shaft and looking down-upon the stack and the motormounted thereon. Figure 4 is a vertical enlarged section through theturret supporting shaft showing a portion of the driving connectionbetween the motor and this shaft. Figure 5 is a vertical section throughthe stack of a modified form of my ventilator. Figure 6 is a. verticalfragmentary section of a switch controlled by the velocity of the `airtraveling through the stack. Figure 7 is an enlarged fragmem tarysectional view thereof. Figure 8 is a vertical section showing anothermodified form of controlling switch mechanism.

Similar reference numerals indicate simiare simple and not liadisclosingthe interior lar parts in each of the several ligures of the drawings.v

In its general organization this invention comprises a stack whichcarries a.y vertical shaft, a turret mounted onthe shaft above the stackand`having a plurality ofpropelling blades or vanesonits outer side,'amotor carried by thestack and driving a `farnand la switch for operatingsaid motor, which switch is actuated'by means responsiveto vthe velocityofthe wind.

The ventilator is adapted to ".be placed'on an'exposed Apart of t-heroof of the lho'use or building being ventilated and is-mounted on anupwardly extending-vent vpipe of :the

ventilating system (not shown) through which the foul air orobjectionable gas is drawn out of the'building and exhaustedlinto theoutside air.

in the preferred form of my invention shown in Figs. L4, the lstack '6'is made 'in the `form-of a. cylindrical sheet metal body and is adaptedto fitover the vent pipe 5 and be secured thereto inf any approvedmanner. The stack vis Vbraced at its vlower end byV a transversechanneled bar 7 which is secured to the diametrically opposite sides ofthe stack by bolts or rivets 8 passing therethrough. This'ba'r alsoserves'to support fthe post 9 upon which :the-turret and ventilating fanare supported; In the upper part of the stack are arranged cross braces10' which are provided at their outer lends with iianges'll which areadapted to be secured to the stack by rivets '12, these braces embracethe post` .9 and are clamped thereto by suitable fasten'ings." A

W'ithin the post is arranged the vvertical driving shaft '13 on theupper end of'which" the turretlli is secured. The diameter ofthis turretis greater thanfthe diameter of the stack 6 and vent `pipe and isprovided on its peripheral edge with a dependingv vertical flange orapron 15, the lower edge of which is lower than the upper edge of thestack 6', thereby preventing the entrance of rain snow vinto the bodyAof the ventilator."y The means for securing the turret tothe vert/ icaldriving shaft lcomprise an upper spid'erlb and alower spider if? securedto yeach ofthese members and `adapted `to" retainA them in lejo- `and atvtheir cent-ral portions axial relation. "Each ofthese spiders is com?posed of ytwo seetiQ'IjlS the central parts `of which are formed .toreceive thev driving'shaft and are bolted together by bolts 18. The arms19 of each section are bent at an angle to the centra-l part and aresecured at their ends to the underside of the turret by bolts 2O or inany other suitable manner.

T he rotation of the turret is accomplished by securing a number ofspaced propeller buckets or blades 2l to the upper inclined face of theconical rot-ary turret. For substantially one-half of the rotation' ofthe turret these propeller blades are traveling with the wind, ofcourse, and the remaining half rotation against the wind. Theconstruction of the blades when traveling with the wind obviouslypresents no difficulty, but to travel against the wind the blades mustbe designed so as to ofier the minimum resistance to the air current.For this'purpose each of the propeller blades has its forward orleadingI edge 22 disposed flush with the upper' surface of the turretand is secured thereto by suitable forwardly extending flanges 23 whilethe main body of eachblade extends rearwardly and upwardly from saidleading edge and terminates in a trailing edge 241. y 1

he central or body portion of each blade is pointed forming a forwardlyand downwardly tapering bucket, the apex 25 of the same being arrangedadjacent the upper surface of the turret. Since all of the blades orbuckets are arranged in the same relation to the turret, the blades onone side of the turret present their concave sides to the wind while theblades on the other side present their conveX sides. The turret,obviously, is rotated in the direction opposite to that direction inwhich the bucket shaped blades open, i. e., 'in the direction of thearrow, as shown 1n Figure 1, by reason of the greater resistance offeredby the blades when arranged in that position than whenarranged in theposition the blades assume on the side of the turret going against thewind, i. e., when the buckets open in the direction of the wind current.This arrangement of the blades effectively ro tates the turnet even whenthe air current is of slight velocity, the action of the same being inVaccordance with accepted pneumaticdynamic practice, the air currentcurling over the trailing edgey 24 when the buckets travel against thewind and effectively killing the vacuum tending to form thereunder.

TheV suction of the foul air through the Ventilating system and outbetween the apron 15 and the stack 6 is accomplished by securing a.considerable number of suction blades 26 in a. circumferential row onthe lower inclined face-of the rotary dome or turret 14;. Each of theseblades are inclined somewhat or arranged obliquelyrelatively'to aperpendicular plane passing through the axis and through saidvsuctionblade soA as to act in the `manner of an ordinaryV propeller blade.

Each of these suction blades is secured at its lower end to an annularstifening ring 27 which is disposed just above and adjacent to the upperedge of the vent pipe 6, the adjacent faces of the stiifening ring andstack being substantially parallel to each other. To ine crease theefiiciency of the fan, preferably two of the suction blades are extendedinwardly toward the aXis of t-he turret forming inner `suction blades28. The lower Aedge of each of these blades 28 is curved forwardlyforining a lower advancing edge 29, thereby causing these blades to actas scoops, throwing the foul air upwardly and outwardly where it isfinally expelled by the other suction blades of the fan.

The vertical central shaft 13 which carries the turret is supporte-dwithin the post 9 by a plurality of annular' ball bearings indicated at30, of any usual and approved construction and at its lower end by athrust bearing (not shown) which is preferably constructed in'accordancewith the application for patent for improvements in bearings filed by meJuly 2,1926, Serial No. 120,058. The shaft and bearings preferabl runina bath of o il which may be supplie through conduits 31, 31 as shownin Fig. 4.

Above this post a beveled gear wheel 32 is mounted on the `shaft 13 soas to freely rotate thereon. This gear wheel, as shown in Fig. 4 isprovided with a depending annular fla-nge 33 within which arearranged anouter annular race 84 which is L shape in cross seetion, asimilar innerrace. 35 and a plurality of ball bearings 86 between these races. Theinner race 35 rests upon a collar 37 which is pinned or otherwisesuitably secured to the shaft 13.` 0n its upper side this" gear wheelisprovided with a` hub 38 having a notch 39 which is engaged by a dog orpawl 40 pivotally mounted on a pin 41 which extends dia` metricallythrough the shaft 18. The notch 39 is so shaped that when the shaft,under wind power, is traveling faster than the gear wheel 32, the dogwill travel idly over the hub, but when the gear wheel is driven, thedog will engage the notch and rotate the shaft and the turret mountedthereon. By this means the yelectric motor is not turned when theventilator is operating solely under wind pressure. Y

The motor 42 is n'iounted on a hed composed of two bars 43 which aresuitably secured to the braces 10 supporting the upper part of the post9. This motor drives a reducing worm gear 44 which is also mounted onthe motor bed and which in turn drives a shaft l5 carryinga pinion 46which meshes with and drives the gear wheel 32 when the motor isenergized. Y

The means .for energizing the motorl when the velocity of the winddrives the turret at less than the desired minimum speed, includes amercury tube switch which is mountedV on one of the arms 19 of thespider 17 supporting the turret. This switch comprises ay hermetically4sealed tube 47 made of' glass or other insulating material, whichcontains a quantity of inercury f1-'8.' This tube is-mounted on the armby vafbracket Y4 9 whichl is so mounted that the jtube'can 'be tipped toa greater or less extent. At its inner end two contacts 50, 50 areprovided which are arranged within the tube and are adapted to bebridged, and the circuit thereby closed themercury. The leads 51 fromthese contacts (are sealed in the gia and extend inwardly along't-he arm19. is ap'iarent that when the tube is inclined vided at the upper endof the post 9, and each ring is connected by a wire 5G to the motor lf2.rThe brushes 53 are received in tubular metal sockets 57 which are setinto a fiber box 58, and to each of the sockets is soldered one of thewires 51 leading through a groove 62 on the shaft 13 to the switch. Thebrushes are. held in Contact with the rings by springs 59. The fiber box58 is supported in a collar 60 which is secured to the shaft 13 andoverhangs the fiber collar 54 to prevent the entrance of dust and dirtinto the post 9. The line or wire 61 supplying the current preferablyconi'iects with the motor and extends down the de of the stack and isconnected to any suitable source 'of power within the building.

1t is apparent from the foregoing description that while the. turret isrotated rapidly by wind power, held at the upper end thereof. lVhen thewind dies down to a point where it does not drive the turret at asuiiicient speed, the` mercui-y falls back in the tube, closes thecircuit and starts the motor. If the wind again picks up, the mercury isthrown to the outer end of the tube and the circuit is broken. Ifdesired, a ridge or obstruction 98 may be placed in the tube to hold themercury in the outer end of the tube untilthe turret travels at lessthan the speed it is driven by the mot-or and at the lower end until thewind drives the turret substantially faster than the motor driven speed.

1n the modified form of my invent-ion shown in Fig. 5 a separateelectrically driven fan 63 is provided, and is adapted to be operatedwhen the wind dies. In this form the stack 6 is made somewhat longerthan in the preferred form, and at the lower end thereof below the post9 which supports the turret an electric motor 64 is supported by arms65.

the mercury 1n the tube isv The shaft of the motor is arrangedvertically and afjthe:lowerend thereof. is mounted afan G B'havingradially extending blades 66 which are adapted to force the 'air up thestack when the motor is energized. be actuated by the switch shown inthe prefoi-red construction through wires 67 extending upwardly alongthe post 9, or it may be controlled by the velocity of the airtravelling through the stack by means of one oft the switch mechanismsshown in Fi 6-8.

Various means may be employed for utilizing the velocity of the foul airtraveling through the stack to actuate the switch controlling the motor.Figs. 6 and 7, a U-tube 68 is arranged on'the exterior of the stack 6within an enclosing casing 69, the inner `branch 79 of which is eX-tended inwardly through the stack and formed to provide a downwardextension 71, which opens againstthe flow of air through the stack. vThe`U-tube contains a quantity of liquid 72 having non-freezing andnonevaporating qualities, and in the outer branch 7 3 is arranged a.float 74 actuating a vertical J plunger 7 5. At the upper end of thetube is mounted a fiber collar 76 through which pass vertical bolts 77on diametrically opposite sides of the tube, one of which passes througha fiat spring 78 which carries a contact 79 adapted to engage the headof the other bolt 77. Each of the bolts 77 carries a nut 8O at its lowerend and serves as a binding post for the wire 81 leading through thestack 6 to the motor. -When the air is passing through the stack at lowvelocity, the switch is closed as shown in Fig. 7, and the motoroperated. `When the wind picks up and creates a greater flow through theStack a pressure is created at the inner end of the U-tube, which raisesthe float 74, and they contact 79 and breaks the circuit.

The controlling deviceshown in Fig. 8 comprises a small propeller 82such as are employed in anemometers, which is mounted within asupporting rim 83 so as to be rotated by the air passing up the stack.The movement of this propeller is transmitted to a horizontal shaft 84by a pair of beveled gear wheels 85, 86 which shaft extends to theexterior of the stack and rotates a vertical shaft 87, through beveledgear wheels 88, 89. Both of these shafts are suitably journaled in abracket 90. A horizontal arm 91 is mounted on the upper end of thevertical Shaft 87 and at one of its outer Vends this arm carries amercury tube switch 92 similar to themercury tube switch 47 in thepreferred construction, and in the same manner as in the preferredconstruction, a circuit is established between the switch and the motorby leads 93, brushes 9-1, contact rings 95 and a double wire 96connected with the terminals of the motor.

In this construction, as the wind picks up and air is sucked morerapidly through the This motor may In the form shown 1n stack, thepropeller 82 is revolved more rapidly which in turn revolves the arm 91more rapidly and forces the mercury aWay from the contacts Within themercury tube switch thereby stopping the mot-or; and When the Wind diesdown, the propeller and arm are rotated less rapidly and the mercurytube closes and energizes the motor, thereby insuring a minimumVentilating effect at all time c All of the several forms of thisinvention provide a rotary ventilator which operates continuously toventilate the building regard-y less of the Wind pressure. The electricmotor, however, operates only a small fraction of the time andconsequently uses but a small amount of current to secure this result.This result is also accomplished in a simple and effective manner, theparts are adequately protected from th-e Weather, and the flow of airthrough the ventilator is not appreciably Checked by the electricdriving mechanism.

I cl aim as my invention:

l. In a ventilator, the combination of a revolving Wind driven member,an electric motor, a Ventilating fan driven by said motor7 a switchmounted on said Wind driven member and actuated by centrifugal force todeenergize said motor When said Wind driven member is rotated fasterthan a predeterminedl speed and means for adjusting said switch to varysaid predetermined speed.

2. In a ventilator, the combination of a revolving Wind driven member,an electric motor, a Ventilating` fan driven by said motor, a switchpivotally mounted on said Wind driven member and actuated by centrifugalforce to deenergize said motor when said Wind driven member is rotatedfaster than a predetermined speed and means for adjustably moving saidswitch about its pivotal connection to vary said predetermined speed.

In testimony whereof I hereby ailix my signature.

WILLIAM F. HIRSGHMAN.

